Report by Captain Josiah Holman, who had been engaged by the Company in March 1862. The report is dated 11 June 1868.
J. H. Miller, Esq., Manager of the Cadiangullong Copper Mining Company (Limited), Sydney.
SIR, – In compliance with your request, I now forward you a brief report on the above property, County of Bathurst.
LAND. – The property consists of 564 acres 2 roods 25 perches, situated on the East side of Cadiangullong Creek, and 1014 acres 1 rood 36 perches on the West side, forming a block 1579 acres 0 roods 22 perches, having its longest sides parallel with the bearings of the Copper Lodes. The creek furnishes a constant supply of good water.
BUILDINGS. – These comprise a manager’s house 30 by 60 feet, upwards of 60 huts suitable for officers and workpeople’s residences, a few of the latter built of slabs with shingled roofs, the remainder of slabs and bark roofs, two hotels and three stores, chiefly the property of the company; also a public school standing on an acre of land belonging to the Government, and a chapel; the foregoing forming the building of an irregular township.
Smelting Works. – The large shed covered with galvanised iron is 125 by 60 feet, under which are three copper ore furnaces, one roasting furnace and a refinery furnace. One ore smelting furnace and the refinery are complete, the others having had their bottoms recently taken out, will require rebuilding above the foundations. The ironwork of these is complete, and the whole of these furnaces could quickly be put in efficient working order. A detached galvanised iron covered shed 60 by 50 feet, contains one new copper ore smelting furnace complete, by having a new bottom. A detached galvanised iron shed, 35 by 25 feet, covers a calcining furnace. Detached is a smith’s shop with forge, anvil, vice and tools; also sets of smelting tools for immediate resumption of works. An assay office built of slags, with shingled roof 29 by 18 feet, contains two furnaces, assay tools, scales, weights, crucibles, chemicals and fluxes for assaying, with office furniture, stationery, &c, &c. One of Avery’s large weighing machines and a weighbridge used for weighing the fuel for the works.
The quantity of copper ores smelted at the works has been 7695 tons 12 hundred weight and 3 quarters, yielding a gross produce in refined copper of 837 tons 11 hundred weight and 6 pounds, viz: from East Cadia Mine 1341 tons 8 hundred weight; West Cadia 5164 tons 7 hundred weight 1 quarter, together estimated to yield 772 tons 16 hundred weight 1 quarter 17 pounds of copper and purchased ores from Canoblas Mine 871 tons 16 hundred weight 1 quarter; Carangara Mines 318 tons 5 hundred weight 1 quarter; and having produced as above stated 837 tons 11 hundred weight 6 pounds of refined copper. These works are capable of reducing over 300 tons of copper ore monthly.
MINES. – The East Cadia Mine has been explored to a depth of 23 fathoms only, at which horizon the great vein bearing both copper ores and gold has been proved to be fully 60 feet wide. It is well defined, and has very little underlay. This enormous vein has been developed at the twenty-three fathom level for an extent of only about twenty fathoms on the run of it, and driven across its whole width of over sixty-six feet, in which parallel zones of the vein stone yielded native copper, thinly dispersed through the iron stone, while other zones of iron pyrites yielded gold almost to paying quantities as tested at the Sydney Mint. The ground at these points is remarkably easy and expeditious for developing the vein. The chief obstacles that presented themselves while testing the vein of this depth was the large influx of water that soon overpowered the eight-horse power portable engine that pumped the water, and the short tenure of the lease held by the company making the trial.
The superficial deposit of copper ores discovered on this lode produced splendid specimens of red oxide of copper, thinly studded with the native metal. These ores were surrounded by others of lower quality; however, 1341 tons 8 hundred weight of ores were raised, and estimated to yield 123 tons and 16 hundred weight 1 quarter 2 pounds of fine copper, and averaging 0.23 per cent.
Both the surface and deeper works here have given ample evidence of the existence of gold throughout this unusually large lode, and, independent of its offering encouraging prospects for giving large returns of copper when developed to greater depths, I have great confidence that the vein, abounding in iron and iron pyrites, traversing the whole length of the property, will ultimately be found to produce gold in payable quantity, and inexhaustible in its supply of auriferous stone.
The engine shaft is vertical, and its position is right for testing the vein to a great depth.
WEST CADIA MINE – NORTH SECTION. – Upon this a 12-horse power portable engine is in position on Trevena’s Engine Shaft, adapted to pumping water and hauling stone. The shaft is 10 fathoms deep, having an adit drainage at 19 fathoms deep; a drive 12 fathoms below this where the 3 1/2-inch plunger lift of pumps is used, and a 6-inch drawing lift 9 fathoms below, reaching to the bottom of the shaft. At the deepest point the lode has been cross-cutted only and found to be poor. At 12 fathoms below adit the drive has been extended west of the shaft on Northey’s lode 63 fathoms, and having a tramway laid therein. The adit level has been driven west of shaft on Northey’s lode 95 fathoms, and has a tramway laid for over 100 fathoms leading out to the ore dressing floors. The 13 fathoms level over adit has been driven west on the lode 180 fathoms.
In addition to Trevena’s shaft the following have been sunk to depths varying from 12 to 32 fathoms, viz.: – Rodd’s, Hall’s, Gundry’s, Samuel’s, John’s and old engine shafts all sunk on the course and underlay of Icely’s and Northey’s lodes.
The slate rock contiguous to these lodes, but merging into granite at a little distance, is easy and expeditious for the rapid extension of this section of the mine, which hitherto has yielded nearly 3000 tons of copper ores.
WEST CADIA – SOUTH SECTION. – Has had erected thereon the Cornish condensing engine of twenty-five-inch cylinder, with ten-ton boiler, having pumping, winding, stone-breaker, crusher rolls, and jigging machinery connected thereto. The engine and crusher are fixed in strong masonry work. Near these are the smithy, with two forges and requisite tools, a large carpenter’s shop, and engine fitting shop, with large lathe and other useful tools, powder magazine, mining office, and furniture, &c., &c.
PHILLIP’S ENGINE SHAFT has been sunk thirty-two fathoms deep, having yielded rich ores from the surface to the deepest point reached. In this shaft a column of eight-inch pumps extends down to the twenty-six-fathoms level, at which depth the drives have been extended only twenty fathoms in length, in a large portion of which the lode yielded four tons of fine yellow sulphurets of copper of over 20 per cent. The sixteen-fathoms level has been extended west of this shaft into the hill side on the course of Jones’ lode seventy fathoms, and communicated with Lawson’s and Want’s shafts at a depth of twenty-five fathoms from surface, and large quantities of good quality copper ores have been produced at these sections.
Further east, on Baker’s and Clark’s lodes, several shafts have been sunk to depths varying from six to fifteen fathoms deep; from all quantities of good quality ores have been produced up to the recent closing of the mines. Over 2000 tons of rich ores have been produced from the south section of West Cadia; and the total produce of copper ores from the north and south sections has been 6164 tons 12 hundred weight 1 quarter, yielding by assay 640 tons 15 pounds of fine copper, giving an average of 12.366 per cent, on the ores returned.
SUSPENSION OF THESE MINES. – This was caused chiefly by the extraordinary low prices, then prevailing in the English markets for copper, to an inadequate capital to develop the mines on a large scale, and to a partial falling off in the quantity and quality of the ores produced latterly from the mines.
FUTURE DEVELOPMENT. – The West Cadiangullong Mines are well provided with all requisite machinery of a heavy kind for years of work, all of which is ready for immediate duty. They are provided with iron tramways, tools, and materials for present action, and this portion of the property fully warrants an extended exploration by the raising of a capital of £10,000, and judiciously expended therein justifies me in holding out the expectation that it would be the means of opening up a permanently remunerative Copper Mining property.
THE WEST CADIANGULLONG GREAT IRON LODE should at least be practically tested on a small scale by stampers to arrive at the auriferous value of the stone, which, if remunerative, should be developed on a grand scale.
QUARTZ REEF. – This has been tested on a small scale to the south of the Iron Duke Hill, where some very good specimens of auriferous gossans were found; but the trials stopped short of satisfactorily opening up the vein at this point. At a short distance south-east a large quartz vein crops out for a great distance, but it has not been tested. It is then lost sight of on the flat, but again crops out near to Hick’s Hotel, east of the creek, where a shaft was recently sunk on it to a depth of twenty feet, displaying the reef fully four feet wide, composed near surface of ferruginous quartz, the latter giving an increased yield of pyrites in depth. Gold could be seen sparingly in this stone, and half-a-ton of this average stone forwarded to Sydney and crushed and tested at the Mint gave a yield of nearly half an ounce of gold in a ton of stone. This result is nearly, if not quite, payable by working it on a large scale. This reef fully warrants a deeper trial. I am, sir, your obedient servant,
JOSIAH HOLMAN, Mining Captain.
It is interesting to note some of the reasons for the closure of the mine. These factors affected the viability of each and every mine. While market price volatility was a chief cause in this case, limited capital is also mentioned. The falling off in quality of the ores after initial discoveries would normally have been expected and was at least partially factored into the development of the mines at Cadia, so that a mixture of ores was always available for smelting. The report makes clear that a lack of exploration in advance of mining was not a factor that had led to the closure of the mines, though more could have been done had the opportunity arisen.